I really wanted to take advantage of the monsters as PC's in 3E, to the point that I actually gave XP bonuses to people who started with a new character rather than raising their old one. So we've had Drow, Tielflings, Half-Celestials, Yuan-ti, Bugbears and Half-Dragons.

I only played one non-standard race. A Neutral lizardman cleric. the campaign only lasted two sessions though - not becasue fo the monster PCs but just general disinterest in the game (2nd edition AD&D).

Other than that I don't allow non-stadard PC races although I am going to include some of the alternate human races in the Scarred Lands DM Screen Companion. Great little supplement and screen though the art on the side the players have to look at is simply awful.

"Patriotism is the last refuge of the scoundrel." - Samuel Johnson 18th century English author.

"Everything must be at once for six month old puppies, 6 year old children and gamers of any age"

"I asked Dave to please send me his rules additions, for I thought a whole new system should be developed. A few weeks after his visit I received 18 or so handwritten pages of rules and notes pertaining to his campaign, and I immediately began work on a brand new manuscript. "Greyhawk" campaign started —the first D&D campaign! About three weeks later, I had some 100 typewritten pages, and we began serious play-testing in Lake Geneva, while copies were sent to the Twin Cities and to several other groups for comment. DUNGEONS & DRAGONS had been born."
— EGG, Dragon #7

IMC, orcs, hobgoblins, goblins, kobolds, lizardmen, and similar races are all valid pc choices. The only limits I set are ecl. You can't use a creature whose ecl would put you over the limit for the group, and all monster races must have a class. Everyone seems to enjoy it.

Flesh, Blood & Magic: The Biothaumaturgist's Handbook - In Development"...the red-armoured warrior watched the tides of the battle, face hidden from view by his visor such that he seemed like an impassive sentinel watching the vagaries of fate."
- Red Talon, Carnifex's Story Hour